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The new hardiness map’s obsolete! The new hardiness map’s obsolete!

I posted back in January about my excitement about the update of the USDA Hardiness zone map. While I acknowledged some of the shortcomings of the new map, I was excited because it was a big improvement over the old map, both in terms of content (more recent temperature data included) and presentation (interactive search features, better graphics).

Dr. Nir Krakauer, assistant professor of civil engineering in The City College of New York’s Grove School of Engineering, was less impressed, however, and has essentially declared the new hardiness map dead on arrival. Dr. Krakauer conducted his own analysis of climatic data and determined that much of the country is already a half zone to one full zone warmer than the new USDA map. Why the difference? The USDA zone estimates were based on a simple average of annual minimum temperatures from the past thirty years. Dr. Krakuar’s applied a regression analysis to account for more recent warming. One of the key observations of the new analysis is that winter minimum temperatures are warming much faster than average temperatures, leading to the new hardiness zone projections.

So, what do we do with this information? All of the limitations that we associate with hardiness ratings still apply. Most landscapes experience micro-climates that may be slightly colder or warmer than the surrounding area. Plus, winter hardiness is just one piece of information in plant selection (we also need to also consider sun exposure, pest pressure, soil factors – drainage, soil pH, and so on). Most importantly, average temperatures don’t kill plants, extreme temperatures do. So whether we look at long-term averages or try to account for the most recent trends; the extreme 1 year in 5 or 1 year in 10 is what will cause issues. For example, if Krakuar’s projection is right and we’re a zone warmer on average, then the greater Lansing area is now zone 6b (0 to -5 deg. F). We’ve been colder than that in 2 out of the last 4 years.

The press release that accompanies Dr. Krakuar’s study starts with an attention-getting line: “Gardeners and landscapers may want to rethink their fall tree plantings.” But really things haven’t changed that much from the past. How homeowners and landscapers use zone information is still a matter of risk tolerance. If I chose a zone 5 plant and we’ve really warmed to zone 6, I’ve lost nothing. If I gamble and plant zone 6 plants and we drop back down to -10 or -15 deg. I may be looking for replacements. And, of course, there’s the tendency of many gardeners to ‘push their zone’, so we may have folks trying to grow zone 7 plants in Lansing. Which is fine – as long as people understand the risk. Actually I think a better approach to hardiness zones may be a probability rating: Are you willing to take a 1 in 10 chance your plant won’t make it? 1 in 4? 50-50? As new climate data are added to the model, garden centers could post and update the odds, sort of like the latest line at a sports book in Vegas. Those that want the ‘tried and true’ can stick with the old zone 5’s; those that want to live on the edge can pay their money and take their chances.

The good, the bad, and the ugly. A reply.

Ginny Stibolt of the Florida Native Plant Society recently posted Native Plant Issues: The good, the bad and the ugly, featuring me as the ugly. I posted a reply on her post, which I include here. To keep things in context, I encourage you to read her post first.

Enjoy your weekend!

Hi Ginny:

Some comments and a few points of clarification.

On the first item, as a Federal agency the USDA is bound by the Executive Order on Invasive Species which defines natives as species that occur in an ecosystem “other than as a result of an introduction”. I suspect they tried to simplify the language for the National Planting day release when they substituted ‘naturally occurring’.

On the Arbor Day Foundation, I am fairly certain they use contract nurseries in various locations for their tree sales. In any event, they have plenty of trained foresters on their staff that understand the importance of provenance and they would not send trees from northern seed sources to Florida or vice versa. But I certainly can’t fault the idea of supporting the Arbor Foundation, declining their trees, and buying trees from a local nursery.

On the Google + Hangout discussion no one was ‘booted off’. These were straight and simple technical issues. If people watch the Youtube video, the audio sounds like Neil Armstrong on the moon. This is a new technology for most of us and we are dealing with some growing pains. I would have much preferred even numbers on each side. Having an imbalanced debate can work against the majority, too. As Wilt Chamberlain famously observed, “Nobody roots for Goliath.” That said, we did have a lively and cordial debate and I hope people will bear with the grainy images and tinny audio and take a look.

Kentucky coffeetree

I haven’t watched the video but I don’t think I said there were no natives that could be used as street trees here in Michigan. If I did, I misspoke. That might be true for Linda in the Northwest – if you look at the native tree list for King county you’d be hard pressed to find anything that could be recommended in good conscience as a street tree. We have a few more options here in Michigan. If we were looking for a street tree for Lansing or Detroit the list could include hackberry, honeylocust, Kentucky coffeetree, tulip poplar, swamp white oak, and red maple. But even this list makes urban foresters cringe because they think red maples are already over-planted, tulip poplar is weak-wooded, and hackberry is difficult to transplant. With regards to Mary Wilson’s comments, there is a distinction between street trees and landscape trees. Landscape trees could be anywhere on a residential or commercial landscape where they could receive irrigation or other care so there is broader list, in contrast to street trees found on street sides in tree lawns or tree pits. Street trees are subject to the ‘worst of the worst’ in terms of environmental conditions; minimal rooting volume, compacted soils, road salt, and reflected heat load; but they provided the ‘biggest bang’ in ecosystem services, especially cooling buildings and sidewalks.

Swamp white oak

This has been an interesting discussion and clearly I have touched a nerve. I have to confess I have never been vilified so much in my life, which has been a little discomforting but also strangely flattering. When I met with Jeff and Linda earlier this week Jeff commented, “Wow, I’ve never been able to sit across the table from the devil incarnate before!” Fortunately, I work in academia where we spend most of our days telling one another how stupid the other is. People that seek to avoid criticism generally don’t do well in this line of work. Peer review forces us to critically examine our statements and sharpen our arguments. I was pleased and gratified to see some of the changes proposed for FNPS website and literature – why leave ‘low hanging fruit’ around for critics? While I didn’t appreciate some the comments made about me, if I’ve caused this group and others to strengthen their arguments and re-examine some of their assertions regarding natives, then the slings and arrows I’ve taken these past couple weeks haven’t been in vain.

Poisoned bird seed and trust

Over the years I’ve said some nice things about Scotts Miracle-gro products, such as one of their potting soils, and some not so nice things, such as with their Round-up resistant Kentucky bluegrass. I’ve never thought of them as a particularly good or particularly bad company, just a company trying to do the best it could while being reasonably honest about what it was doing (You could argue that they tried to pull something fancy with the Round-up resistant Kentucky bluegrass, but I’m going to give them the benefit of the doubt and say they were just exploiting an obvious governments loophole – not exactly good, but hey, it’s a dog eat dog world out there).

But then the news broke that they had applied insecticides illegally to their wild bird food products, falsified pesticide regulation documents, distributed pesticides with misleading and unapproved labels and distributed unregistered pesticides. If you haven’t seen the article yet you need to look here.

Damn.

Anyone who has read much of what I write knows that I try to tell the truth about products to the best of my ability, to do this I rely on a lot of different sources of information, including information provided by the company itself. I trust that, for the most part, companies try to do what they say they’re doing (or not doing) in terms of letting us know what’s in their products. At the least I assume that they follow the government’s rules and regulations.

This is a serious breach of my trust.

How am I supposed to deliver the facts about Scotts Miracle-Gro products when I can’t trust them to do what they say they’re doing?

I mean really? How can I talk about their products again? I have no idea what’s in there.

I’m trying to think of something pithy to say next – but I’ve got nothing. I’m deeply disturbed that this could happen, and, at least for the time being, I just can’t, in good conscience, trust this company or its products. Sure, the company is saying all the right things now, but that’s not enough.

Here’s a thought – maybe they could publicly state that they’re not going to release the Round-up resistant Kentucky bluegrass – you know – to prove that they really are serious about avoiding doing things that might disturb the environment. And then actually do it. Yes – that would be a good start.

Wandering in the Woods

This past week a friend of mine, Carol Reese, an Extension Specialist at the University of Tennessee (and one of my favorite speakers), told me that she’d like to post a little something about natives. I said sure, no problem, just send it along. And she did. But before posting it sometime next week, I thought I’d post another article that she sent along — one that isn’t quite so sciency and which will let you get to know Carol before you hear what she has to say about natives.

As a side note — Carol was bitten by a copperhead in the foot this past year — had to be given 10 units of anti-venom. From what she’s told me she has recovered to almost 100%.

Wandering in the Woods

by Carol Reese

Every morning at dawn, my dog Junebug jumps on the bed and approaches my sleeping form. My eyes slit open to see her just inches away, staring intently at my face. The instant we meet eyes, she bounds happily off the bed and runs around the bedroom, loudly rousting the rest of the dogs, who thump their tails, stretch, yawn, and come to the edge of the bed to see if Junebug is telling the truth about me being awake. I’m allowed one quick cup of microwave coffee, though the flapping of the dog door drives me crazy as they run in and out staring at me impatiently. Why they won’t go on without me isn’t fully understood, but for some reason, they want their slow two footed friend to go, too.

I live on an old farm, and though it’s not mine, I feel as though I’m kin to this land. I am, I guess, since, if I were to fall and molder into this ground, my flesh would be recycled into the plants and the animals that feed on them. That thought makes me comfortable most anywhere, but here, there’s more to make me feel at home. Old farms like this have a lingering sense of long-gone eras and of the people who lived here before. The old Ford Jubilee tractor still sits in an outbuilding, looking identical to the one on the farm in Mississippi where I was raised. Predating that, is a large horse collar hanging in the old barn. The kinfolks tell me it was worn by a Percheron, used for pulling logs from the woods. I imagine the old days, the big horse comfortable in the rolling green pasture, woods for shade, and a lake for drinking.

The dogs and I are drenched by dew these spring mornings. The woodland phlox are almost finished blooming along the edge of the woods, and the bearded tongue (Penstemon) is just beginning to peak. Wild azaleas and dogwood were blooming earlier, but now it’s the bell-like clusters of the tree huckleberry, the tallest member of the blueberry family. The many native ferns are hitting their glory days, and along a sunny creek bank, I come across American wisteria (Wisteria frutescens) and a native clematis (Clematis crispa) This clematis will have wiry blue hanging blooms with four pointed petals that curl back like a rolled up hat brim. Further, in a sunny field, I find oxeye daisies and coreopsis. Though the milkweed and butterfly weed is not blooming yet, I see two monarchs cartwheel among them. Looks like butterfly hanky panky to me, and I will look
here later in the summer for the bold striped monarch caterpillars that feed on those species..

Grinch, my little schnauzer mix, suddenly arches high up off the ground and comes down with both front paws in perfect diving form. Dirt sprays as she digs ferociously at the ground where a mole made the earth bulge. Nearby, I notice several clumps of foliage that were covered with little light pink striped flowers earlier this spring. It’s Claytonia virginica, or spring beauty. With a sharp stick, I pry up the tuber beneath the foliage. It’s one of the wild foods that I find pretty good, either raw or cooked, tasting to me like a cross between water chestnut and boiled peanut. (My brother says they taste like dirt to him!) The dogs assume I must know something they don’t, like the whereabouts of the mole, so they jostle up next to me, ears pricked. A couple of them are willing to help me dig, but don’t take offense when I refuse the offer. I get a pocket full
and we ramble on to more important business. There’s a blue grosbeak nest I’m keeping free of cow bird eggs.

The dogs’ tails sink with disappointment when I turn back, except for the old ones, who have taken to plodding along behind me instead of ranging as they did in years past. One day I’ll have to bury them and let their bodies enrich the meadows they so enjoyed exploring. Another day in the future, some other person will walk this farm and rediscover the pleasures in these fields. It’s a kind of immortality, isn’t it?

Fearless fall color predictions

Happy Labor Day! Hopefully everyone had an enjoyable 3-day weekend. Labor day is the unofficial end of summer, which means fall is just around the corner. In fact, fall may be a little early this year around these parts. We are already starting to pick up some fall color – mainly maples, sassafras, and sumac. I usually get some calls from various media outlets asking for predictions on fall color. It’s always a dicey proposition. Weather going into fall is certainly a factor for fall color, but conditions during the fall itself are the final trump card. As I noted, we’re likely to see an early fall here in the Upper Midwest and, if we don’t start getting some decent rain, I suspect it could be a relatively short season as trees begin to drop leaves early due to continuing drought stress. Of course, all this can change relatively quickly if we get into a different weather pattern.

July 28, 2012. Sumac in fall color near DeWitt, MI.

Speaking of fall leaf color, the Fall Color Guy (aka Dr. Howard Neufeld, Appalachian State Department of Biology) has started his annual reports. http://biology.appstate.edu/fall-colors . This site is a great resource if you’re planning on doing some leaf peeping in the Appalachians. And even if you aren’t, I still recommend this site as one of the best on the biology of leaf color.

Tomatoes, Dingleberry Deer, and the Goose Poop

Do you ever get annoyed right after you eat a nice, ripe, homegrown tomato at those little pieces of tomato skin that get caught in your teeth, or even against the roof of your mouth? Sure, the tomatoes are worth it, but those little pieces of skin can drive me up the wall for hours afterwards, especially after eating a bunch of cherry tomatoes.

This post is about how I learned to get rid of those little tomato bits.

It all started a few weeks ago when I posted about a new type of bag that you could put on your fruit to protect them from insects, animals, or whatever. You can see that post here.

Anyway, since that time the deer have come again and again to my garden, and they have targeted all of my almost but not quite ripe tomatoes. Unless you’ve experienced it, it’s impossible to imagine the frustration of going out one evening and seeing a bunch of tomatoes just starting to change color, and then the next morning going out to see them again – and they’re all gone.

Fortunately for me, the tomatoes that I put bags around were saved from deer.

The tomatoes above were protected by bags — overall they worked well

The funny thing was, about a quarter of the bags that I used for bagging those tomatoes went missing. I figured that was no big deal though. The tomatoes probably just aborted for some reason, the bags fell, and the wind blew them into the neighbor’s yard – not my problem anymore!

And then I saw this huge piece of goose poop out on the lawn not too far from the garden. Now don’t get me wrong, goose poop is no big deal – usually I don’t notice it at all– but this was such a big pile that I couldn’t avert my eyes. After a week or so of having this pile of poop sitting in my yard I had had enough. Even though it had rained, this pile just wasn’t disappearing.

So I went over to investigate.

Goose poop, or the leavings of an evil deer?

As you may have already guessed, it was a bag that I had protected one of those tomatoes with. I could tell from the red flecks inside that it had held a beautiful red tomato. Some dingleberry deer plucked that bagged tomato off the plant and sucked out the yummy guts of the tomato while leaving the nasty skin behind.

And that’s how I learned to get rid of the skin from my tomatoes.

For those participating in the discussion tomorrow

For those people participating in the discussion on Google + tomorrow I just wanted to let you know that I will be inviting you to participate in a "hangout" a few minutes before the discussion is scheduled to begin. You will need to be on Google + to see and join this hangout. If for some reason you don’t see it, go to hangouts on the left side of the screen. Once you get to the hangouts screen you’ll see hangouts to join and this one should be there! If you haven’t used hangouts before, you need to try one between now and when we start so that you can be sure your computer is set up properly.</d

Update on Google +

For all of you getting ready to participate with us on Google + on Thursday I need to get you into our circle, so if you could either search for me on Google + and friend me, or, alternatively, e-mail me (gillm003@umn.edu) and let me know you want to participate, that will be necessary for your participation.

We are planning to record this session and make it available on you-tube (assuming I can figure out all the technology).

I have been told by a few people that my scheduling stinks because many of you work. I hear you loud and clear! Next time we’ll try to do this in the eveni

So, what’s your point?

My recent post on Seattle Public Utilities proposed restriction on the use of non-native plants for landscaping drew the ire of Taryn Evans of the Florida Native Plant Society. Taryn was critical not only of what I had to say but how I said it. She felt that my post was ‘clumsy’ and lacked a clear focus. In my defense, part of the perceived lack of clarity may stem from a lack of context. I alluded to several previous blog posts (including the references to using goats and schoolchildren to control invasives) but didn’t include the links – which are now listed at the end this post.

In terms of my other points, let me state my views as succinctly as possible.

I support promoting the increased use of natives in landscapes as part of an overall effort to increase landscape diversity and stability. Part of this is based on the notion that a diverse landscape –including natives – is buffered against various environmental and biological perturbations. But I also support natives because they provide a linkage to our native environment or sense of place. This second argument, by the way, is adopted by the California Native Plant Society http://www.cnps.org/cnps/about/ but is dismissed by Tallamy who states that his argument for native plants “moves beyond debatable values and ethics and into the world of scientific fact.”

I do not support legal restrictions that mandate the use of native plants in landscapes

Here are my concerns:

– The “scientific facts” regarding natives are not universally accepted by ecologists and are subject to debate as well. http://www.nature.com/nature/journal/v474/n7350/full/474153a.html#/ref8 A species’ need for water/nutrients/pesticides is a function of the environment in which the species evolved and not necessarily a native/non-native question. Invasiveness is an undoubtedly an issue, but exotic does not mean invasive. Some will argue that we can hedge our bets and prevent future invasions by planting only natives. And that is a justifiable position – I don’t agree with it – but I accept it as a rational argument. The dilemma with banning all exotics is that we throw the baby out with the bathwater and risk eliminating many useful plants.

– Natives can make great landscape plants in the right place but in many cases they are poor choices, especially in the built environment. Consider some of Tallamy’s recommendations from “Bringing Nature Home”:

Cottonwood. Cottonwoods are banned by many tree ordinances for their mess (cottony seeds and sticky buds) and are weak-wooded.

Maples. Maples are great landscape trees but we need to consider the fact that they are already overplanted in many communities. If we look at street trees and other public trees, maples make 50% or more of the tree population in some cities and towns. Does planting more make sense in these situations?

Ashes. Maybe if you live west of the Rockies, otherwise they’re a non-starter.

Lindens. Lindens have great form, growth rate and color. Unfortunately they are candy to Japanese beetles.

Elms. A handful of Dutch elm disease tolerant cultivars of American elm are available but the vast majority of trees available are Eurasian hybrids.

– Plants, especially trees and shrubs, evolve slowly. If we accept current climate predictions, trees planted today may experience very different climates in their lifetimes than those under which they evolved. The widespread outbreak of pine beetle (a native pest) in the Mountain West that is destroying millions of acres of pines could be an early indicator that changes in climate are already increasing stress levels and reducing the fitness of native trees.

Taryn was also critical of the tone of my post. For me and my co-bloggers this space is the editorial page of our lives. The blog is an opportunity to let our hair down a bit, vent on pet peeves, and sometimes shoot from the hip and play agent provocateur. No one likes to be criticized but it comes with holding our ideas up to public scrutiny and I accept that. I should note, however, that as the native debate moves from advocacy and education to codes and regulation, native advocates need to brace for increased criticisms and have their logical and scientific ducks in a row – which is the take-home theme of my post. Let’s face it, my critique was mild. As seen in the repsones to my post, some are quick to politicize or label the native case as disingenuous. Others would go further still and have labeled nativists as reactionaries and xenophobes (See http://arnoldia.arboretum.harvard.edu/pdf/articles/646.pdf or wade through David Theodoropoulos’s “Invasion Biology: Critique of a Pseudoscience). Obviously this is taking the argument to a ridiculous extent. I’m all for a fair debate where we can question statements and ideas but not motivations.

Earlier posts:

Are natives the answer?

Controlling invasives with schoolchildren

Controlling invasives with goats

Get Ready for Something New

Over the past week the garden professors have been playing with something new, and we think it’s time to try it live with all of you.

Hopefully some of you are aware of Google and Google +. On Google + there is a feature called “Hangouts” which lets you interact directly with up to ten people at once using camera and microphone. More than that can participate by watching the discussion (though I’m still working that out on my computer — it should be ready by the time we go live.)

Next Thursday August 30 at 11:20 Eastern, 10:20 Central, 9:20 Mountain, and 8:20 Pacific time we’re going to start a hangout on Google + and invite all of you to join. Then we’re going to start a live discussion.

The topic of the discussion is related to, but not exactly the same as, Bert’s somewhat controversial post from last week — “Should the government be able to require you to plant natives on your own land.”

As a side note, if you want to read how the Florida Native Plant Society responded to that post please read this. Wow! Even though the topic we’ll be discussing doesn’t deal with Bert’s post directly, hopefully someone (or a few people) from the FNPS will join us. I’ll drop a comment onto their blog to make sure they at least know about the opportunity.

We are open to tangents in the discussion. We want this to be open ended, fun, and informative.

So what do you need to do if you want to participate? For right now the thing to do would be to get a google + account. Just go here. Also, if you don’t have a camera or microphone hooked up to your computer — now would be a good time to do that. We’d also appreciate it if you’d comment on this post to let us know that you are planning on participating (or want to participate but can’t make it). Please keep in mind that if we don’t have much participation we probably won’t try this again — at least not for awhile.

We’ll provide more instructions and information on the blog as we get closer to next Thursday. We’re looking forward to this and hope that many of you can join us.